Granulomatous appendicitis is defined as the presence of granulomatous inflammation in the wall of the appendix. Other causes include foreign bodies, obstruction secondary to a faecolith, mucocele, tumor and diverticulitis rarely .[1] In the presence of granulomatous appendicitis it is important to exclude systemic causes of granulomatous inflammation by appropriate investigations and long-term follow-up. We present a case of isolated granulomatous inflammation of the appendix.

Case report

A 15yrs old male presented with complaints of pain in the right iliac fossa of one-week duration. He had mild tenderness in the right iliac fossa. Ultrasound was reported as thickened appendix suggestive of appendicitis. He underwent a laparoscopy which revealed a mass arising from appendix around 7x4 cm size 9, mimicking a mucocele with thickened caecum and ileum with multiple regional lymph nodes enlarged.

An open limited ileo-caecal resection was done along with lymph node excision. Cut open specimen showed a fleshy tumor of the appendix obliterating the entire lum en(Figure 1). Mucosa of the caecum and terminal ileum appeared normal. Postoperative period was uneventful. Histopathology showed granulomatous inflammation of the appendix (Figure 2). Lymph nodes showed granulomatous inflammation , colon had few granulomas in the mucosa and small bowel showed no specific lesions. Subsequently the following work up was done in view of the histopathological diagnosis.

PCR for mycobacteria , chest x-ray and mantoux test was negative. Angiotensin converting enzyme levels for sarcoidosis was normal 20U/L (8-65 U/L). Immunoglobulin levels for toxoplasmosis and schistosomiasis were within normal limits IgG 4 (6<) & IgM 0.6 (<0.8). Stains did not reveal any parasitic infections. CT scan of the abdomen and colonoscopy was normal with no features of Crohn’s disease. Hence the diagnosis of idiopathic granulomatous inflammation of the appendix was concluded.

Discussion

Granulomatous inflammation of the appendix is uncommon. The reported incidence in western countries ranges from 0.14-0.3%, with an incidence of 1.3-2.3% in under-developed countries.[2] Epitheliod granulomas are known to occur in the gastrointestinal tract in association with a number of systemic granulomatous conditions and infections. More recently two etiologies have been recognized that potentially account for idiopathic cases of granulomatous appendicitis. The first is infection by pathogen Yersinia species.[3] The second may be most commonest of all, namely sub acute/recurrent appendicitis with interval appendectomy.[3] This condition likely produces a granulomatous reaction in relation to a protracted secondary inflammatory response to appendicitis and temporizing measures to delay appendectomy such as antibiotic therapy. The higher incidence in the underdeveloped countries is believed to be due to the increased incidence of tuberculosis and shistosomiasis.[2]

The presence of granulomas in an appendix specimen should prompt a search for Crohn’s disease elsewhere in the bowel,[4] but only 5-10% of patients with granulomatous appendicitis develop Crohns disease elsewhere in the gastrointestinal tract. Crohn and Ginzberg in 1932 in their initial description of regional ileitis stated that the process never transcends the limits of Bauhin’s valve, and that the appendix is always spared.[5] However, a number of subsequent studies have suggested that the appendix can be involved alone or in association with Crohn’s disease of the ileum or colon.[6]

Other causes of granulomatous appendicitis need to be considered. Sarcoidosis can manifest as acute appendicitis.[7] The Kveim test is positive in 80% of patients with this condition. Mycobacterium tuberculosis is diagnosed by tissue culture, demonstration of acid-fast bacilli, positive tuberculin skin tests with evidence of pulmonary or additional systemic involvement. Yersinia pseudotuberculosis can cause enteric infections with granulmatous lesions of the mesenteric lymph nodes, terminal ileitis, and or appendicitis.[8]